Surf lifesavers have had to move their patrolling area because of the erosion.

Scott James, who filmed the rescue, told 3 News erosion had made the beach a lot more dangerous in a short amount of time.

He posted on Facebook: "Unfortunately this being a tourist didn't know the seriousness of the situation. He's really lucky. [St] Clair is dangerous for the locals [who] know what to do but could be deadly to [a] tourist and kids who have no idea."

The Dunedin City Council is installing temporary measures to try and protect the beach from further erosion.